The chemical and dynamical evolution of the galaxy

I develop theoretical models of the chemical and dynamical evolution of galaxies and present a Galactic structure survey-invaluable tools for uncovering the history of the formation of our Galaxy. Important advances in my theoretical models are non-instantaneous recycling of newly synthesized elements such as iron from Type Ia supernovae (mergers of white dwarf binaries). I incorporate Type Ia supernovae in models of baryonic dark matter as stellar remnants. If dark halos consist mainly of white dwarfs, as has been proposed, then an excessive supernovae rate is predicted unless the binary fraction was virtually zero. The observed chemical abundance ratios of halo stars signify enrichment from only Type II supernovae. I explore the timescale for the onset of Type Ia supernovae as an upper-limit to the timescale of halo formation. The apparent inconsistency between differences in ages of halo stars (2-3 Gyr) and timescale inferred from Type Ia supernovae ({dollar}sbsp{lcub}sim{rcub}{lcub}<{rcub}{dollar}0.1 Gyr) suggests galaxies formed from hierarchical substructure. I calculate chemical and dynamical evolution models of viscous disks with non-instantaneous recycling. Patterns of element ratios and scatter in the age-metallicity relationship are predicted throughout the disk. Characterized by radial flows of gas, these models are ideal for exploring new ideas on creating the Galactic bulge from disk inflow. The high metallicity of bulge stars may not require an ad hoc variation of the stellar initial mass function if inflow alters the apparent yields in the bulge and solar neighborhood. I present an unbiased, magnitude-limited spectroscopic survey of F-G stars. Radial velocities accurate to {dollar}sbsp{lcub}sim{rcub}{lcub}<{rcub}{dollar}10 km/s are derived and compared with predictions of Galactic structure models. Distances are derived by photometric parallax, and 3-dimensional velocities are calculated using published proper motions. Calibration of spectral line strengths against metallicity is presented for standard stars. Evaluation of metallicities of program stars is forthcoming. These data will be useful for constraining the existence of a metallicity gradient in the Galactic halo, and determining correlations between kinematics and chemistry in the disk/halo transition.